package com.sky.service.impl;

import com.sky.context.BaseContext;
import com.sky.dto.ShoppingCartDTO;
import com.sky.entity.Dish;
import com.sky.entity.Setmeal;
import com.sky.entity.ShoppingCart;
import com.sky.mapper.DishMapper;
import com.sky.mapper.SetmealMapper;
import com.sky.mapper.ShoppingCartMapper;
import com.sky.service.ShoppingCartService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import java.time.LocalDateTime;
import java.util.List;

@Service
@Slf4j
public class ShoppingCartServiceImpl implements ShoppingCartService {

    /**
     * 添加购物车
     * @param shoppingCartDTO
     */
    @Autowired
    private ShoppingCartMapper shoppingCartMapper;
    @Autowired
    private DishMapper dishMapper;
    @Autowired
    private SetmealMapper setmealMapper;

    /**
     * 添加购物车
     * @param shoppingCartDTO
     */
    @Transactional
    @Override
    public void addShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        //判断当前加入到购物车中的商品是否已经存在了
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);
        shoppingCart.setUserId(BaseContext.getCurrentId());
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        //如果已经存在了，只需要将数量加一
        if (list != null && list.size() > 0){
            shoppingCart.setId(list.get(0).getId());
            shoppingCart.setNumber(list.get(0).getNumber()+1);
            shoppingCartMapper.updateNumberById(shoppingCart);
            return;
        }
        //如果不存在，则需要重新插入一条数据 ，先判断添加的是菜品还是套餐
        Long dishId = shoppingCartDTO.getDishId();
        if (dishId != null){
            Dish dish = dishMapper.getById(dishId);
            shoppingCart.setName(dish.getName());
            shoppingCart.setImage(dish.getImage());
            shoppingCart.setAmount(dish.getPrice());

        }else {
            Setmeal setmeal = setmealMapper.getById(shoppingCartDTO.getSetmealId());
            shoppingCart.setName(setmeal.getName());
            shoppingCart.setImage(setmeal.getImage());
            shoppingCart.setAmount(setmeal.getPrice());

        }

        shoppingCart.setNumber(1);
        shoppingCart.setCreateTime(LocalDateTime.now());
        shoppingCartMapper.insert(shoppingCart);
    }

    /**
     * 查看购物车
     * @return
     */
    @Override
    public List<ShoppingCart> showShoppingCart() {
        ShoppingCart shoppingCart = ShoppingCart.builder()
                .userId(BaseContext.getCurrentId())
                .build();
        List<ShoppingCart> shoppingCartList = shoppingCartMapper.list(shoppingCart);
        return shoppingCartList;
    }

    /**
     * 清空购物车
     */
    @Override
    public void deleteByUserId() {
        shoppingCartMapper.deleteByUserId(BaseContext.getCurrentId());
    }

    /**
     * 删除购物车中的一个商品
     * @param shoppingCartDTO
     */
    @Override
    @Transactional
    public void subShoppingCart(ShoppingCartDTO shoppingCartDTO) {
        ShoppingCart shoppingCart = new ShoppingCart();
        BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);

        shoppingCart.setUserId(BaseContext.getCurrentId());
        List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);
        if (list == null && list.size() == 0){
            return;
        }
        ShoppingCart currentShoppingCart = list.get(0);
        if (currentShoppingCart.getNumber() == 1) {
            shoppingCartMapper.deleteById(currentShoppingCart.getId());
        }else{
            currentShoppingCart.setNumber(currentShoppingCart.getNumber() -1);
            shoppingCartMapper.updateNumberById(currentShoppingCart);
        }


    }
}
